196 GREENHOUSE PLANTS. 



grows with great rapidity upon the stems and leaves, causing 

 them to decay and fall off very quickly, to the great dis- 

 turbance of the health of the plant, and the entire destruction 

 of its beauty. The best preventive that we know of is 

 flowers of sulphur dusted carefully over the parts affected, at 

 the earliest moment that the fungus is observed ; this may be 

 done either with the fingers, or from a small dredger or box 

 with a perforated top. The best means to prevent the 

 occurrence of mildew is to keep the leaf-action and root-action 

 properly balanced, by avoiding extremes of heat and moisture 

 on either side. 



WATEEING AND WATEE. 



HE best time of the day to water greenhouse 

 plants, during the summer season, is the evening ; 

 but in the autumn and winter months, midday is 

 preferable. As a general rule plant-growers give themselves 

 very little trouble about the quality or temperature of the 

 water applied to their plants. The result of this want of 

 thought is, that in many instances the temperature of the 

 water may be several degrees lower than that of the house, a 

 condition which is most injurious to the plants, affecting their 

 well-being to a much greater extent than most persons 

 imagine. To obviate this, the water tanks should have a 

 branch pipe passed from the heating apparatus through or 

 beneath them, so that the water may always be kept as warm 

 as the atmosphere in which the plants are growing ; if it 

 should be even a few degrees warmer so much the better. 

 When, however, a pipe is thus passed through the tank, it 



